--Description: The curl-like polarization pattern (B-modes) of the cosmic microwave background is a powerful probe of primordial gravitational waves, and an integrated measure of large-scale structure out to high redshift along the line of sight. The B-modes could also be generated by other sources, such as cosmic birefringence and primordial magnetic fields. For a few years, POLARBEAR is putting together large telescopes with sensitive detectors to target the faint B-mode signals, for which I will show the recent analyses and measurements. At infrared wavelengths, signatures from the first stars and galaxies could be detected by a few ongoing experiments, such as CIBER, which is a rocket-borne instrument that can probe the absolute spectrum and spatial anisotropy of the extragalactic infrared background. I will discuss various infrared emission components that complicate studies of the first stars and galaxies, especially, an excess power of the infrared emission at large angular scales. Finally, I will talk about the extragalactic gamma-ray background anisotropy and discuss constraints on dark matter properties using the Fermi-LAT and Planck data sets.